Second room and connecting it with the first

As you can read in the title of this tutorial we want to create a second room now and connect it with the first one we have already built. So, load the mapfile of the last tutorial.
Either you can do another room by hand (good for practicing) or we can just copy the first one. For this action select the whole room with all lights (neither the box, nor the player deathmatch) and press the spacebar.
Now pull the copied room to the right handside, out of the first room, and be sure that both have the same height:

Deselect everything and select all 4 walls like I did:

Now reduce the width in the ZX window:

Copy the walls and put them across from the others:

It should look like this in the camera view:

Deselect all walls. Now we have to build the floor which connects both parts. For this, create a brush as high as the floor we already have in our rooms and as wide as the gap between the copied four walls. After that press t and select the same texture like we have for our other two floors:

Do the same for the trim and the walls:

Only the ceiling is missing, now. Copy the floor of the crossing and put it higher until it fits with the gap between the two upper trim brushes:

Now we have two rooms and a crossing between them. But before you compile your map you should change the two false textures of the upper trim brushes into the ceiling texture. Press shift+Ctrl+Alt" and select the two faces of the brushes.
They should be red now, but without white borders. Press t and select the right texture.

Here you can get the maps for this tutorial (place it into baseq3/maps):